public inbox for linux-arm-kernel@lists.infradead.org
 help / color / mirror / Atom feed
From: Vladimir Oltean <vladimir.oltean@nxp.com>
To: Robin Murphy <robin.murphy@arm.com>
Cc: devicetree@vger.kernel.org, iommu@lists.linux.dev,
	Laurentiu Tudor <laurentiu.tudor@nxp.com>,
	Will Deacon <will@kernel.org>,
	linux-arm-kernel@lists.infradead.org,
	Shawn Guo <shawnguo@kernel.org>, Li Yang <leoyang.li@nxp.com>,
	Rob Herring <robh+dt@kernel.org>,
	Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
	linux-kernel@vger.kernel.org, Michael Walle <michael@walle.cc>
Subject: Re: [RFC PATCH] arm64: dts: ls1028a: mark ARM SMMU as DMA coherent
Date: Thu, 5 Jan 2023 14:04:47 +0200	[thread overview]
Message-ID: <20230105120447.vnr24pusr3ihdhwk@skbuf> (raw)
In-Reply-To: <67ae3a53-3db9-c1bc-2b67-08df14bc15cc@arm.com>

On Tue, Jan 03, 2023 at 06:12:29PM +0000, Robin Murphy wrote:
> > I have a side question, why is the dev_name() of your SMMU set to
> > "arm-smmu.0.auto" (determined by PLATFORM_DEVID_AUTO if I'm not mistaken)?
> 
> This is an ACPI-based machine, where platform device discovery and creation
> is... different :)
> 
> SMMUs are among those managed by drivers/acpi/arm64/iort.c
> 
> > I'm asking because I would like to study the mechanism through which
> > your SMMU platform device get probed, to make sure that it's not
> > possible, during shutdown, for both platform_driver :: shutdown()
> > and platform_driver :: remove() methods to get called by the driver core.
> > This is generally not disallowed, and even possible if the entity who
> > registers these platform devices has its ->shutdown() method pointing
> > at ->remove().
> 
> Yikes, I'd very much hope that that's not a thing!

Ah, ok. Appears to be fine. Looking at drivers/acpi/arm64/iort.c,
it seems that no one is removing those platform devices.

_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

      reply	other threads:[~2023-01-05 22:58 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-12-08 15:15 [RFC PATCH] arm64: dts: ls1028a: mark ARM SMMU as DMA coherent Vladimir Oltean
2022-12-08 19:01 ` Robin Murphy
2022-12-14 16:53   ` Vladimir Oltean
2022-12-14 20:33     ` Robin Murphy
2022-12-19 12:16       ` Vladimir Oltean
2023-01-03 18:12         ` Robin Murphy
2023-01-05 12:04           ` Vladimir Oltean [this message]

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20230105120447.vnr24pusr3ihdhwk@skbuf \
    --to=vladimir.oltean@nxp.com \
    --cc=devicetree@vger.kernel.org \
    --cc=iommu@lists.linux.dev \
    --cc=krzysztof.kozlowski+dt@linaro.org \
    --cc=laurentiu.tudor@nxp.com \
    --cc=leoyang.li@nxp.com \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=michael@walle.cc \
    --cc=robh+dt@kernel.org \
    --cc=robin.murphy@arm.com \
    --cc=shawnguo@kernel.org \
    --cc=will@kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox